M&M’s chocolate and movies challenge

After Virgin’s “Exercise your muscle” and Absolut’s “Bottle Search“, it’s now time for M&M to challenge us with “50 Dark movies hidden in a painting“. Recently launched in the US, the advergame features a Rembrandt’s style painting with a series of visual riddles. Players have to move around the screen and find 5o movie titles represented by the characters populating the painting.

Definitely an hard challenge which, strangely enough, does not have a competition attached. Even if you solve all the riddles, you win nothing but glory. Interesting decision. I wonder if this is the best thing to do when you want to generate buzz around a game and boost players collaboration and user-generated content around it.

I would like to know the agency behind it, anyone can help?
Game found via Saw a good idea.